Endoscopes are primarily used to visually examine parts of the body including the stomach, colon, intestine, and esophagus. In order to view an inner portion of the body, the medical professional will insert the endoscope into a patient through an orifice.
At the handle portion of the endoscope are a number of controls for deflecting the tip of the endoscope that is within the patient. Such deflection allows the medical professional to better view the bodily interior. The medical professional normally manipulates the control features of the endoscope by holding the handle at chest level with his/her right hand.
In addition to deflecting the tip of the endoscope by using the control handle, the medical professional also rotates the endoscope in order to move to and better view an area of the bodily interior. For example, when used orally, the medical professional rotates the device by having his/her free hand hold a portion of the endoscope just outside the patient's mouth and turning his/her hand from side-to-side. It is difficult for the medical professional to turn the endoscope to any great degree because the medical professional is limited by the degree of rotation that his/her wrist can turn. Once the medical professional reaches that limit, the medical professional must stop and re-grip the endoscope in order to further rotate the device.
A medical professional can also rotate the device by fully extending the potion of the endoscope that remains outside the patient and then turning the device by twisting the hand that is holding the handle of the endoscope. However, the medical professional has less precision when rotating the device in this manner.
The medical professional cannot maintain the rotated position of the endoscope without using his/her hand (or another person's hand) to hold the endoscope in place. This results in the medical professional losing the ability to perform other functions with that hand.